Ed Sheeran revealed a story about when Eminem tested Kendrick Lamar's lyrical ability to see if he was using a ghostwriter.

Sheeran talked about a conversation he had with Rick Rubin after he helped produce the MMLPII.  Rubin told him about Eminem testing Lamar in the studio.

“He arrived and Kendrick came with all his mates and Eminem said, ‘I just want you in the studio, just you on your own and then my engineer is gonna come in and then record you doing it, but your mates aren’t allowed in,'” he recalls. “And then, Kendrick did it and wrote a sick verse. And then everyone came in to listen to it and Eminem said that he did it to test Kendrick because he thought he had a ghostwriter. And, he then realized that he didn’t, and then claimed he was the best, which is kinda cool I think.”

That's the kind of test that you only get one chance at.  The best part about the story is that Eminem was obviously convinced that Lamar was legit, because Kendrick was the only artist to appear on the MMLPII album.

Check out his feature on 'Love Game' below.